242 BACTERIOLOGY 



Bouillon. Becomes slowly turbid, with a slight stringy sediment. Nitrates 



reduced to nitrites. 

 Habitat. Water. 



100. B. devorans Zimmerman. 



Bak. Trink. u. Nutzwasser, Chemnitz, 1890. 



Morphology. Bacilli 0.7 : 0.9-1.2 /u, ; occur singly and in pairs and chains. 

 Gelatin colonies . Deep colonies: small, white. Surface colonies : round, white, 



granular to filamentous ; yellowish gray, margin fringed. 

 Gelatin stab. In depth, growth filiform, with a bubble above, under which 



there is a whitish growth. The funnel forms without visible liquefaction, 



with growth along the walls of the funnel. 

 Agar slant. Growth thin, gray, spreading. 

 Habitat. Water. 



101. B. aquatilis Frankland 



Zeitsch. f. Hygiene, VI, 1889, 381. 



Morphology. Bacilli 2.5 //,; filaments 1 7.0 JJL long. Grow very slowly in the 



usual culture media. 

 Gelatin colonies. Surface colonies show yellowish brown centres, from which 



twisted yellowish brown filaments are given off. 

 Gelatin stab. In depth, growth scarcely visible at first ; liquefaction begins 



later, then progresses more rapidly; on the surface, a small yellowish 



colony. 



Agar slant. Growth glistening, yellowish, limited. 

 Potato. Scarcely any growth, or a faint yellowish lirce only. 

 Habitat. Water. 



102. B. diffusus Frankland 



Zeitsch. f. Hygiene, VI, 1889, 396. 



Morphology. Bacilli 0.5-1.7 ju,; filaments. 



Gelatin colonies. Deep colonies : round, granular, with erose edges. Surface 



colonies: thin, bluish gray, spreading. Microscopically, granular, erose- 



edged; a central nucleus, with a pale blue, irregular-edged, outer zone. 

 Gelatin stab. Growth only on the surface, which is thin, glistening, grayish 



yellow ; the gelatin is slowly liquefied. 



Agar slant. Growth thin, glistening, light yellow to creamy. 

 Bouillon. Turbid, sediment grayish yellow, with flocculi on the surface. 

 Potato. Growth thin, glistening, smooth, greenish yellow, titrates slowly 



reduced. 

 Habitat. Earth. 



